Variable speed transmission device



- y $5, 1940? D. HEYER Y 2,207,219

VARIABLE SPEED TRANSMISSION DEVICE Filed Aug. 12, 1955 s Sheets- Sheet 1ATTORNEY July 9,1940. D, HEY 2,207,219

VARIABLE SPEED TRANSMISSION DEV ICE.

Filed Aug. 12, 19:55 6 Sh e ets-She et 2 o I V v K w o A90 7 Z/ v l o) Oi v x4 2 0 z/ 2 Q 23). I ATTQZ/VEY July 9, 1940'; y b. HEYER 2,207,219

VARIABLE SPEED TRANSMISSION mavrcm I Ffiled Aug. 12, 1935 eShets-Sheet'l':

%. 6.. 4 [/VWZ/VTOQ BY ATTORNEY y 9, 1940- DJHE'YER 2,207,219 VARIABLESPEED TRANSMISS ION DEVICE I I Filed Aug. 12, 1955 s Sheets-Sheet 4 n9Il 164 I ms 1 I76 7 m 1 2 I5 I [55 r [a7 16? 9 is 160 9/6 I79 v 9INVENTOR. j u He at BY /o v ATTORNEY.

July' 9, 1940. v HEYER I 1 r 2,207,219

VARIABLE SPEED TRANSMISSION DEVICE I Filed Aug. 12, 19:55 a Shets-Sheet5 INVENTOR. D n all W BY o H e ATTORNEY;

Jul 9, 1940.

D. HEYER VARIABLE SPEED TRANSMISSION DEVICE Fild Aug. 12, 1955 6Sheets-Sheet 6 lath n30 10/ 10a Yul,

I I I I mum E l l 6 I a/ \:I:;;//

K 1/9 E ua INVENTOR. 9 fl ATTORNEY.

Patented July 9, 1940 UNITED STATES VARIABLE SPEED TRANSMISSION DEVICEDon Heyer, Los Angeles, Calif., assignor to U. S. Electrical MotorsInc., Los Ans'eles, Calif., a corporation of California ApplicationAugust 12, 1935, Serial No. 35,819

9 Claims.

This invention relates to an adjustable speed power unit, and moreparticularly to an integral construction incorporating anelectric motorin driving relation to a driving pulley structure, a

driven pulley structure in driving relation to a load driving shaft, anda belt for transmitting power from the driving pulley structure to thedriven pulley structure, at least one of the pulley Structures having anadjustable efiective pulley diameter, whereby the variation in speedratio is obtained.

, Such an adjustable pulley structure may indriving belt. In order to.provide means for: ad-

justing the effective diameter of the pulley structure, the pulleysectio'nsare made relatively axially adjustable. In this way theinclined faces can be brought closer together, causing the belt to beurged radially outward to produce an increased efiective diameter; orthey can be separated, causing the belt to contact with the inclinedfaces at a shorter radial distance to produce a decreased effectivediameter.

The variable speed transmission may have two adjustable pulleystructures, or itmay include one adjustable pulley structure'and onepulley having a fixed efiective diameter. When only one adjustablediameter pulley structure isemployed, the belt may be maintained inactive driving relation to the pulleys by adjusting the center distancebetween the axes of the two pulleys in accordance with the adjustment ofthe adjustable pulley structure. When two adjustable pulley structuresare employed the pulley structures are arranged to be oppositelyadjustable, that is, an increase in efiective diameter of one of thepulley structures is accompanied by'a compensating decrease in theefiective diameter of the other of the pulley structures.

Such variable speed transmissions have been described in several of myearlier applications, which can be identified as follows:

Don Heyer, Variable speed transmission device, Serial No. 631,533, filedSeptember 2, 1932;

Don Heyer, Variable speed power unit, Serial No. 640,707, filed November1, 1932;

Don Heyer, Variable speed drive with multiple belts, Serial No. 667,379,filed April 22, 1933;

Don Heyer et al., Variable speed power Serial No. 679,034, filed July 5,1933;

Don Heyer, Ventilated variable speed power unit, Serial No. 711,917,filed February 19,1934;

Don Heyer, Variable speed power unit, Serial unit,

'NO. 747,410, filed October 8, 1934.

Some of the structure disclosed but not claimed in the presentapplication is made the subject matter of these applications.

In many variable speed power applications it is'desirable to enclose thevariable speed transmission within a protecting casing to protect thebelt and pulley mechanism from dirt, moisture, and other harmfulmaterials; or to prevent the inadvertent entrance of foreign objectsinto the mechanism of the transmission. The practicability of variablespeed transmissions of the type enclosed is dependent upon the life ofthe driving belt, and the ease with which the adjustment of the belt andpulley structures may be effected, and the accessibility of these partsfor replacement or repairs. It is accordingly one ,of the objects ofthis invention to providean enclosed variable speed power unit in whichmeans are provided for so supporting and enclosing the pulley structuresand the driving belt, that the belt and pulley structures are readilyaccessible for replacement, adjustment or repairs.

In one of the embodiments of the invention to be described hereinafter,the adjustable speed transmission is provided with a pair of adjustablediameter pulley structures. One of the pulley structures is directlymounted on the driving shaft of the driving electric motor, and theother pulley structure is directly mounted on the driven shaft,

, which is provided with a load driving extension projecting to theoutside of the enclosing casing. The frame of the driving electric-motoris also supported by the casing enclosing the pulley structure. I

It is another object of this invention to provide an enclosed variablespeed power unit, in

which the driving electric motor together with the driving pulleystructure may be assembled as -a unit and entered into the assembly ofthe variable speed power unit as a, single element, and in which thedriven pulley structure together-with the load driving shaft may beassembled as a unit and entered into the assembly of the variable speedpower unit as a single element.

' In another embodiment of the invention which is described hereinafter,the shaft of the driving electric motor is directly coupled to thedriving shaft of the adjustable speed transmission, and

coupled to the driving motor; but in which it is not necessary to removethe driving motor from its supporting structure during adjustment,replacement or repair of the parts of the variable speed transmission.

This invention possesses many other advantages, and has other objectswhich may be made more easily apparent from a consideration of severalembodiments of the invention. For this purpose there are shown a fewforms in thedrawings accompanying and forming a part of the presentspecification. These forms shall now be described in detail,illustrating the general principles of the invention; but it is to beunderstood that this detailed description is not to be taken in alimiting sense, since the scope of the invention is best defined by theappended claims.

Referring to the drawings:

, Figure 1 is a plan view of an adjustable speed power unit, embodyingthe invention;

Figure 2 is a plan view, similar to Figure 1, illustrating the manner inwhich the positions of the driving electric motor and of the loaddriving shaft may be interchanged;

Figure 3 is a plan view, partly in section, of the variable speel powerunit of Figure 1, with the cover of the enclosing casing removed;

Figure 4 is a side elevation, taken from the front of Figure 3;

Figure 5 is a vertical sectional view taken along the axis of the drivenpulley structure of the variable speed power unit;

Figure 6 is a vertical sectional view taken along the axis of thedriving electric motor and of driving pulley structure of the variablespeed power unit;

Figure '7 is a plan view, partly in section and with the cover of theenclosing casing removed, of another form of variable speed power unitembodying the invention;

Figure 8 is a side elevation taken from the left hand side of Figure 7;

Figure 9 is a side elevation taken from the right hand side of Figure 7,and partly in section taken along the plane 99 of Figure '7;

Figure 10 is an end view, partly in section, taken from the right handside of Figure *8;

Figure 11 is a side elevation taken from the right hand side of Figure7-, and with the cover of the enclosing casing removed, illustrating themanner in which the driving belt may be removed; and

Figure 12 is an end view, partly in section, taken from the right handside of Figure 11.

Referring more particularly to the form of the invention disclosed inFigures 1 to 6, inclusive,

the adjustable speed power unit I is provided with the driving electricmotor 2, having the frame 3 and a rotor which is in driving relation tothe motor shaft 4. The motor shaft 4 has mounted thereon the adjustablepulley structure 5, which by means of the belt 6 drives the adjustablepulley structure 1, mounted on the driven shaft 8. The driven shaft 8 isprovided with the load driving extension 9, which projects to theexterior of the casing Ill, enclosing the belt and pulley structures.

The driving motor 2 is supported on the casing ID by means of the motoradapter bracket H, which casing also supports the means for adjustingthe effective diameter of the driving pulley structure. The casing Illis in turn provided with appropriate feet 12, whereby it may be securedto a supporting foundation.

The driving pulley structure 5 includes the pulley sections l2 and I3,which are suitably splined to the motor shaft, as by means of the key M.The pulley section 12 may be secured to the motor shaft by the set screw15, which passes through the pulley hub and which engages the shaftsurface. The effective diameter of the pulley structure is adjusted bymoving the pulley section 13 toward, or away from, the pulley sectionl2. I3 is adjusted by means of the axially adjustable bearing housingI6, Figure 6, which engages the bearing l1, secured to the hub of thepulley sec- The axial position of the .pulley section The bearing 11also provides means for rotatably supporting one end of the motor shaft4.

The other end of the motor shaft is supported by means of a bearingsuitably secured within the end bell 20 of the motor.

The driven pulley structure includes the pulley sections and 26,whichare in driving relation to the driven shaft. The pulley section 25is provided with the long bushing 21, which is suitably splined to thedriven shaft by means of the key 28. The pulley section 26 may in turnbe suitably splined to the bushing 21. The bushing 21 has the bearing 29secured thereto, which provides means for axially adjusting the pulleysection 25. The, bearing 29 is held within the axially adjustablebearing housing 30, which, in turn, is supported by the control housing3!.

The axial position of the bearing housing 30 is adjusted by means of therotatably supported lead screw 32, which threadedly engages the bearingcap 33 of the bearing housing. The lead screw has an end projectingoutside of the casing to which the manipulating hand wheel 34 issecured. It is obvious from the construction that a rotation of the handwheel 34 and of the lead screw secured thereto results in acorresponding axial adjustment of the bearing housing 30 and of theassociated pulley section 25.

If it is desired, the pulley section 25 may be axially fixed to thedriven shaft. However, in the present instance the pulley section 26-provides means for compensating for belt wear and for determining theinitial belt tension. For this purpose the hub of the pulley section isprovided with the pin 35, which passes through appropriate slots formedin the driven shaft and in the bushing 21. The pulley section 26 isurged into contact with the driving belt by means of the compressionspring 36, which is interposed between the screw plug 31 and the pin 35.The

35 is used, a hole being provided in the shaft to accommodate it. Inthis case the pin serves to restrain the pulley sections against axialas well as rotary movement relative to the shaft. 7 Suitable means areprovided for interlocking the adjustment of the driving and drivenpulley structures. In the present instance the forked lever 38 isprovided, which is pivotally supported on the extending ear 39 of thecontrol housing 3|, and which engages the oppositely positioned pins 48,secured to the bearing housing 38-. The control housing 3| is providedwith the slots 4|, which permit the axial movement of the pins 48, butwhich prevent the rotationof the bearing housing. By means of theconstruction provided an axial movement of bearing housing 38 results ina pivotal movement of the forked lever 38.

The movement of forked levers 2| and 38 is ihterlocked by the commonpivot pin 42, which is detachably secured in the lever 38, as by acotter pin I89, and which engages the slotted end 43 of the lever 2|.The forked levers 2| and 38 may be so proportioned that an increase inthe effective diameter of one of the pulley structures results in acompensating decrease in the effective diameter of the other pulleystructure.

It is obvious from the construction that the effective diameters of thedriving and driven pulley structures are simultaneously adjusted to varythe speed ratio of the variable speed power unit, when the lead screw 32is rotated by the manipulation of the hand wheel 34.

The adjustment of the speed ratio may be indicated by the speedindicator 44, which is removably secured to the control housing 3|, andwhich is actuated in accordance with the axial position of the bearinghousing 38. The manner in which the speed indicator is actuated by theaxial adjustment of the bearing housing 38 has been described in detailin several of my copending applications identified above One end of thedriven shaft 8 is supported bythe bearing 29, which is held within thebearing housing 38. The other end of the driven shaft.

is supported by the bearing 45, which is held within the bearing housing48, formed bythe pass through the flanged member and which are threadedinto the wall of the casing.

To provide means whereby the belt and pulley structures may be readilyremoved from the enclosing casing, the casing I8 is provided with theremovable cover 5|, which is removably secured to the casing by thestuds 53, which engage the tapped holes 54 formed in the main body ofthe casing, and the nuts 52, which are threaded to the studs. As isillustrated by Figures 3 and 4, the cover member 5| joins the main bodyof the casing along the plane of the axes of the driving and drivenshafts. Thus as illustrated by these figures, when the cover member 5|is removed, substantial access may be had to the belt and pulleystructures. To provide access to the pulley structures for inspection orlubricationof the pulley parts, the cover member 5| is prodriven shafts.

together with the radial surfaces 58 and 51 form the annular groove 58extending around the periphery of the member The member II is supportedon the transmission casing by the engagement of theinternal cylindricalsurface 59 and the radial surfaces 88 and 8|, which are formed partly onthe cover member 5| and partly on the main body of the casing,respectively with the cylindrical surface 55 and the radial surfaces 58and 51, formed on the member II. It is obvious from the constructionthat when the cover member 5| is in place the member II and the motorand driving pulley structure supported thereby are rigidly supported infixed position by the engagement of ,these surfaces.

One end of the driven shaft is supported on the transmission casing bythe control housing 3|. For this purpose the control housing 3| has theinternal cylindrical sm'face 82 and the radial control housing 3| issupported on the trans-1 mission casing by the engagement of thecylindrica1'surface'82 and the radial surfaces 83 and 84, with thecorresponding cylindrical surface 85 and radial surfaces 88 and 81,formed partly on the cover member 5| and partly on the main body of thecasing;

As has been previously set forth, the other end of'the driven shaft issupported on the transmission casing by the bearing housing 48, formedby the flanged member 41 and the bearing cap 48. The bearing housing isaccurately located on the transmission housing by the engagement of theexternal cylindrical surface 88- and the radial surface 89, formed onthe member 41, with corresponding cylindrical and radial surfaces 18 andpartly on the main body of the casing.

As illustrated by Figures 3, 4, 5 and 6, the cover.

member 5| joins the main body of the casing |8 along the plane of theaxes of the driving and Thus when the cover 5| has-been removed, thedriving and-driven pulley structures together with their supportingshafts may be removed from the casing, upon the removal of the commonpivot pin 42, interlocking the adjustment of the two pulley structures.For it is obvious that when the pivot pin 42 is removed,

the hand wheel 34 may be operated to permit the driving belt to becomeslack so that item be removed from one of the pulley structures.

The driving motor 2, together with the driving pulley structure 5, maythen be removed from the casing by lifting the motor in a verticaldirection until the radial surfaces 58 and 51,

. formed on the member clear the corresponding radial surfaces 88 and8|, formed on the main body of the casing. The driven pulley structure,together with the control housing and the driven shaft, may also beremovedfrom the casing, upon the removal of the bolts 58, by lifting thecontrol housing and the shaft in a vertical direction until the radialsurfaces 83 and 84 clear the corresponding surfaces formed on the mainbody of the casing.

It is thus obvious that the entire construction associated with thedriving and driven pulley structures may be each assembled as a unit andenter into the assembly of the variable speed power unit as'singleelements, after which the pivot pin 42 may be put in place to interlockthe adjustment of the driving and driven pulley structures.

It is to be noted that the surfaces formed on the main body of thecasing I8 for supporting the driving motor and the control housingextend half way around the periphery of the annular grooves formed onthe members II and 3|. Thus these members will be rigidly supported onthe casing, even when the cover member 5I is removed. It is thuspossible to perform all of the adjustments of the driving and drivenpulley structures necessary to obtain the correct belt tension and beltalignment, with. the cover member 5| removed; or it is possible toremove the cover member 5| to provide access to the belt and pulleystructures, without the necessity of disturbing the positions of thedriving or driven This cover plate is removably secured to thecasing andis located with respect to the-casing by the engagement of thecylindrical surface 14 and the radial surface 75, formed on the casing,with corresponding surfaces formed on the cover plate I3.

When the cover plate 13 is removed, the aperture provided by theinternal cylindrical surface I4 provides means whereby the drivingbelt 6may be passed over the end of the motor shaft 4, without the necessityof removing the motor from its supporting structure. Thus when it isdesired to replace the driving belt, it is only necessary to lift thestructure of the driven shaft and it is not necessary to disturb theposition of the driving motor, which is generally much more difficult tolift thanthe structure of the driven shaft.

As has been previously set forth, the cylindrical and radial surfaces55, 56 and 51,- formed on the member I I, are in every way equivalent tothe corresponding cylindrical and radial surfaces 62, 63 and 84 formedon the member 3|. The positions of these members may thus beinterchanged within the case. Thus to provide means whereby thepositions of the driving motor and of the load driving shaft may beinterchanged with respect to the casing, the surfaces I4 and 15,provided for locating the cover plate 13, are made equivalent to thecorresponding surfaces I8 and TI, provided for locating the position ofthe bearing housing 46, which supports one end of the driven shaft. Thusas illustrated by Figures 1 and 2, the driving electric motor 2 andthe'cover plate 13 may be interchanged in position with the controlhousing 3| and the flanged plate 41, to adjust the position of the loaddriving extension 9 of the driven shaft with respect to the casing.

In order to provide means for ventilating the transmission casing andthe driving electric motor, the member 3| is' provided with theventilating openings I6 for passing air into the transmission casing,and the motor adapter bracket II is provided with the ventilatingpassages 11 for exair into the motor structure through the ventilatingpassages I8 and IT and which discharges shift fork I8 I the air from themotor structure through the air discharge passage 19 formed in themember II. To permit additional cooling air to reach the interior of themotor, inlets I98 are provided in member I i (see Fig. 3). Air is drawnin through these by fan I8 and mingles with the air being drawn out ofthe casing through openings 11, the mingled air circulating about theinterior of the motor and then being discharged through opening I9.

Another form of the invention is illustratedby Figures 7 to 12. In thisform the variable speed transmission includes the driving pulleystructure 88, mounted on the driving shaft 8!, and which by means of thebelt 82 drives the driven pulley structure 83, mounted on the drivenshaft 84. Each of the pulley structures includes one pulley sectionwhich is axially fixed to its shaft and one pulley section which isaxially adjustable with respect to the fixed pulley section. Thus thedriving pulley structure 88 includes the pulley section 85, which isaxially fixed to the driving shaft 8| by the set screw 86, and thepulley section 8'I, which is splined to the driving shaft by the key 88.Similarly, the driven pulley structure includes the pulley section 89,which is secured to the driven shaft by the set screw 98, and the pulleysection 9|, which is splined to the driven shaft by the key 92.

The axially fixed pulley sections 85 and 89 are oppositely faced andaxially displaced to maintain the belt in substantial alignment. Each ofthe axially adjustable pulley sections 81 and 9| has a bearing securedto the hub thereof, which provides means for adjusting the pulleysection in an axial direction. Thus the pulley section 9| is providedwith the bearing 93, which is axially fixed to the hub of. the pulleysection by the snap ring 94. The bearing 93 is held within the axiallyadjustable bearing housing 95, formed by the flanged members 98 and 91,which are suitably held' together by the screws 98. The pulley section81 is likewise provided with the axially adjustable bearing housing 99,which is in every.

way similar to the bearing housing 95 and which provides means foradjusting the axial position of the pulley section.

Bearing housings 95 and 99 are shifted in an axial direction by theshifting forks I88 and 'I8I, which are held within annular groovesformed on the bearing housings. Thus the bearing housing 95v is providedwith the annular groove 98, formed by the flanged members 96 and 91, andthe bearing housing 99 is provided with a similar annular groove I82. Toprevent the rotation of the bearing h'ousings, each of the bearinghousings is provided with a flatted part, which engages the arms of theshift fork. Thus the bearing housing 99 is provided with the flattedportion I89, which engages the arms of the The speed ratio of thevariable speed drive is adjusted by the rotation of the lead screw I83,which-is 'rotatably supported in fixed axial posi-' tion. Each of theshift forks has a bushing secured thereto, which threadedly engages thelead screw I83, whereby a rotation of the lead screw results in acorresponding axial adjustment of the shift forks and of the pulleysection associated therewith. Thus the shift forks I88 and [M arerespectively provided with the threaded bushings I84 and I85. To providemeans for clamping the threaded bushing to the shift forks, each of theshift forks is provided with a sleeve which is split on one side, andwithin which the threaded bushing is clamped. Thus the shiftfork IN isprovided with the split sleeve I06, which is clamped to the threadedbushing I05 by means of the screw I01. Similarly, the shift fork I00 isprovided with the split sleeve I08 for holding the threaded bushing I04.

To provide means for adjusting the speed ratio lead screw I03 has thehand wheel I64 removably secured thereto. -It is obvious from theconstruction that a rotation of the hand wheel I64 will result in acorresponding axial adjustment ofthe shift forks I00 and IOI, and of thepulley sections associated therewith.

The relative rates at which the effective diameters of the driving anddriven pulley structures must be adjusted if the belt is'to bemaintained at a substantially constant tension, is dependent upon therelative values of the effective pulley diameters. If the two pulleysare of equal effective diameter, then the efiectivediameter of one ofthe pulley structures should be increased at the same rate that theeffective diameter of the other pulley structure is decreased. However,when one of the pulley structures has a greater effective diameter thanthe other pulley structure, then the diameter of the pulley structure,having the greater efiective diameter, must be adjusted at a slower ratethan the diameter of the pulley structure having the smaller effectivediameter, if it is desired to maintain the belt at a constant tension.The relation of the rate' of pulley adjustment to the relativepulleydiameters has been carefully set forth in my co-pending application,Ventilated variable speed power unit, Serial No. 711,917, filed February19, 1934.

Thus in the present instance, to maintain the belt at a substantiallyconstant tension, the lead screw I03 is provided with a pair of threadsof different pitch. In the form illustrated, the driven pulley structure03 has a greater average diameter than the driving pulley structure.Thus the thread I09, which engages the threaded bushing I04, is madewith a finer pitch than the thread IIO which engages the threadedbushing I05. In this way the effective diameter of the driven pulleystructure 83 is adjusted at a slower rate than the effective diameter ofthe driving pulley stru'cture, to maintain the belt at a substantiallyconstant tension.

In order to limit the axial adjustment of the.

shift forks to correspond with the maximum effective diameters of thepulley structures, the lock nuts III .and III! are provided,' whichrespectively engage the threaded portions I09 and I I0 of the leadscrew. It is obviousfrom the construction that, when the effectivediameter of the driving pulley structure has been adjusted to itsmaximum -efiective diameter, theend of the threaded bushing 104- willcome into contact with the lock nut II'I, thereby preventing any furtherincreasing adjustment of the diameter of the driving pulley. Conversely,when the efiective diameter of the driven pulley structure has beenadjusted to its maximum value, the end of the threaded bushing I05 comesinto contact with the lock nut II8, thereby preventing a furtheradjustment in this direction. However, when it is desired to remove thedriving belt from the pulley structures, the lock nuts I" and H8 may bewithdrawn to permit the pulley structures to be adjusted untilthe'driving belt is forced entirely off from one of the pulleystructures.

The threaded bushings I04 and I05 also pro.- vide means whereby thetension of the driving belt may be adjusted. When it is desired toadjust the belt tension, one of the bushings may be released so that itis free to rotate with respect to the split sleeve of the-shift fork.The bushing may then be rotated with respect to the lead screw toadjustthe belt tension. Thus it it is desired to increase the belt tension,the screw I01 may be released to permit the threaded bushing I05 torotate within the sleeve I06. The threaded bushing may then be rotatedto move the shift fork IOI toward the shift fork I00 to increase thebelt tension, after which, the threaded' bushing may again be securedwithin the sleeve by taking up on the screw I01. To provide meanswhereby the threaded bushings may be easily-rotated, each of thethreaded bushings is provided with a wrench engaging portion, such asthe hexagonal part I84, formedon the bushing I05.

In many variable speed power applications, many conditions arise when itis desired to provide both a constant speed drive and a variable speeddrive. 8| may be provided with the load driving extension I83, and thedriven shaft'84 is provided with the load driving extension I82. Bymeans of this construction one member of the driven machine may bedriven at a constant speed by the load driving extension I83 of theshaft BI, and another part of the driven machine may be driven at avariable speed by the loaddriving extension I82 of the driven shaft 84.

In the form of the variable speed power uni illustrated by Figures 7 to12, the variable speed transmission is enclosed within the casing I II,formed by the main casing member H2 and the cover member I I3. The maincasing member I I2 is provided with the opposite faced side walls II 4and I I5, which provide means for supporting the entire variable speedtransmission and the driving electric motor IIG. As illustrated tbyFigures 8 and 10, the side wall I III extends substantially to the topof the casing to provide a surface for mounting the driving electricmotor. The other side wall I I5 extends only to the plane .of the axesof the driving and driven shafts, as illustrated by Figure 11. Thus, asillustrated by Figures 11 and 12, when the cover member H3 is removed,substantial access may be had to the belt and pulley structures. Asillustrated by Figures 8, 9

and 10, the .cover member I I3 rests on top of the side walls I I8 and II5 and on the end walls'of the main casing member II2. Suitable meansmay be providedfor securing the cover member to the main casing memberII2. In the present instance the cover H3 is secured to thewall II4 bythe screws I 85'and to the bearing clamping member I49 by the screwsI86. In order to provide meansfor securing the power unit to thesupporting foundation, the main body of the casing I I2 is provided withthe feet I I9, which extend 'a substantial distance beyond the wall II4to supported" in coaxial relation with the driving shaft 8| by theengagement of the internal! cy- For this purpose the driving shaftlindrical surface I21 and the radial surface I28, formed on thetransmission casing, with corresponding surfaces formed on the memberI2I.

The driving electric motor is provided with the motor shaft I29, one endof which is rotatably supported by the bearing I30, secured within thebearing housing I3! formed on the member I2I, and the other end of whichis rotatably supported by a bearing suitably secured within a bearinghousing formed on the end bell I32. The driving connection between themotor shaft I29 and the driving shaft 8| of the variable speedtransmission is formed by the jaw coupling I33, formed on the abuttingshaft ends. The jaw coupling I33 is so formed that the shafts may bedisengaged by a separating axial movement of one of the shafts withrespect to the other shaft. Thus the driving electric motor may beremoved from the assembly of the variable speed power unit, by removingthe nuts I26, without the necessity of disturbing the position of thedriving shaft 8|; or the driving shaft 8|, together with the drivingpulley structure, may be removed from the assembly of the transmission,without the necessity of removing the driving motor from its supportingstructure.

In order to provide means whereby the driving and driven shafts,together with the pulley structures supported thereby, may be quicklyremoved from the transmission casing, the bearings for rotatablysupporting these shafts are held within bearing housings, which areremovably supported on the main body II2 of the transmission casing.Thus the driven shaft 04 is rotatably supported by the bearings I34 andI35, which are respectively held within the removably supportedbearing'housings I36 and I31. The hearing housing I36 is formed by theflanged member I38 and the bearing cap I39, which are suitably heldtogether by the screws I40. The bearing housing may be provided with thelubricating connection I4I and a suitable lubricant retaining seal forpreventing the escape of lubricant from the bearing housing. The bearinghousing is'accurately located in coaxial relation with the driven shaftby the engagement of the internal cylindrical surface I42, formed on thewall II4, with a corresponding surface formed on the bearing housing. Toprovide means for preventing the rotation of the bearing housing, thepin I43 is provided, which engages the slot I44 formed on the flangedmember I38. In this way the bearing housing I36 may be removed from thesupporting wall II4, by moving the driven shaft 84 in an axial directiontoward the right, as viewed in Figure 7, until the bearing housingclears the internal cylindrical surface I42 formed on the supportingwall.

The bearing housing I31 is formed by the housing member I45 and thebearing cap I46.

. The bearing housing is supported by the internal will be rigidlysupportedarrd held against axial movement; but when the clamping 11 813? removed, the bearing housing is free to .move axially (see Fig. 10).

The driving shaft 8| is rotatably supported by the bearings I53 and I53,which are held within the removably supported bearing housings I54 andI55. Bearing housing I54 is supported on the wall II4 by the engagementof the internal cylindrical surface I55, formed on the wall, witha-corresponding surface formed on the bearing housing, and is heldagainst rotation by the pin I51. The cylindrical surface I56 is in everyway identical with the corresponding surface I42, which supports thebearing housing I36, thus providing means wherebythe positions of thedriving and driven shafts may be interchanged within the casing. Thebearing housing I55 is supported on the wall II5 by the engagement ofthe internal cylindrical surface I58, formed partly on the wall H5 andpartly on a clamping member, similar to the member I 49. The hearinghousing is also provided with' the annular groove I59, which performsthe same function as the annular groove I40, formed on the bearinghousing I31. The internal cylindrical surface I58 is formed with thesame dimensions as the cylindrical surface I21, to provide means wherebythe positions of the driving and driven shafts may-be interchangedwithin the casing.

It is obvious from an inspection of Figures '1 and 9 that, the drivingbelt 82 not only encircles the driving and driven shafts; but that italso encircles the lead screw I03. When it is desired to remove thedriving belt from the pulley structure, it is not onlynecessary to passthe belt over the ends of the driving and driven shafts; but it is alsonecessary to pass the belt over the end of the lead screw I03. In orderto provide means, whereby the driving belt may bereadily passed over theend of the lead screw, the lead screw is supported with-its axis abovethe plane of the axes of the driving and driven shafts. Thus asillustrated by Figure 11, the lead screw is supported with its axisabove the wall II5. One end of. the lead screw is supported by thebearing I60, held within the bearing housing I 6| formed on the wall H4,and the other end of the lead screw is rotatably supported by thehearing pedestal I62, which is removably secured to the top of the wallH5. The bearing pedestal I62 is made of sufilcient height to provide asubstantial clearance between the lead screw I03 and the top of the wallH5. Thus as illustrated by Figure 12, when the bolts IE3, holding thebearing pedestal to the wall are removed together with the pedestal,there is suflicient space between the lead screw and the top of the wallII5 to permit the belt to be passed between these members.

Thus when it is desired to remove the driving belt, or the driving ordriven pulley structure from the assembly of the variable speed powerunit, the cover member II3 may be removed to give access to the shiftforks I and IM and to the clamping members of the bearing housings I31and I 55. 'With the cover removed, one of the threaded bushings I04 or Imay be released within the clamping sleeve of the shift fork, andmanipulated to release the belt tension. The clamping members I49 of thebearing housings I31 andI55, and the bearing pedestal I62 maythen beremoved. With these members removed, the

driving shaft 8| may be moved axially toward the right, as viewed inFigure 7, until the end of the shaft clears the internal cylindricalsurface I56 formed on the wall H4. The entire lifted upwardly to permitthe driving belt to pass driving pulley structure may then be rotatedabout the axis of the lead screw I03, to lift the pulley structure outof main casing member II2,

into the position illustrated by Figures 11 and 12.

With the pulley in this position, the belt may be easily removed fromthe driving pulley'structure, as illustrated vby these figures. then maybe passed between the lead screw I03 and the top of the wall II5,.afterwhich, the driven shaft may be moved axially toward the right, as viewedin Figure '7, to ,clear the cylindrical surface I42 formed on wall H4,and then over the end of the shaft.

To provide means whereby the driving and driven pulley structures may bequickly removed from the assembly of the variable speed power eunit, theforked levers I00 and IOI are made with open ends. Thus when the drivingpulley structure has been lifted into the position illustrated by Figure11, and the belt removed, the pulley structure may be removed from theshift fork bypulling the bearing housing 99 out through the open end I65of the shift fork.

To provide means for indicating the speed ratio adjustment, the speedindicator I66 is provided, which is secured to the wall II I of thetransmission casing. The speed indicator- I66 includes the frame I61, towhich the graduated scale I68 is secured, and the pivotally supportedpointer I69, which is actuated in accordance with the axial adjustmentof the pulley section BI. The pointer I69 is secured to the bushing "Iby the set screw I10, and the bushing I1I is in turn pivotally supportedon the axially adjustable rod I12. The rod I12 is provided with the headI13, which is urged into engagement with the shift fork I00 by thecompression spring I14. The rod is supported for axial movement by theframe I61, but is held against rotation by the pin I15, which engagesthe axially extending groove I16, formed in the rod. The rod I12 alsohas the helical groove I11 formed therein, which engages the pin I18,secured to the bushing I". As has been stated, the bushing "I is securedtothe pointer I69. Thus when the shift fork I00 is moved axially inresponse to the rotation of the hand wheel I66, the resultant axialmovement of the rod I12 results in a pivotal movement of the bushing HI,and of the pointer I69 secured thereto. It is thus obvious that thepointer I69 will beactuated in accordance with the axial ad justment ofthe pulley section 9I to indicate the speed ratio adjustment of thevariable speed drive.

The frame I61 of the speed indicator is remo v ably secured to the wallof the transmission casing by the bolts I19. The speed indicator islocated on the wall of the transmission casing by the engagement of theinternal cylindrical sur face I60 and of the radial surface I8I, formedon the wall II1, with corresponding cylindrical and radialsurfaces,'formed on the frame I61 of the speed indicator. To providemeans whereby the driving motor and the driving pulley $611101 ture maybe interchanged in position with the driven shaft and the driven pulleystructure, the surfaces I80 and I8I, provided for supporting the speedindicator, are made with the same dimensions as the surfaces I21 andI28, provided for..

supporting the driving motor. Thus the driving motor may be supportedeither by the surfaces I21 and I28, or by the surfaces l80 and "II.

I claim:

1. In a variable speed power unit, a pair of The belt pulley structures,at least one of said structures having a variable efiective diameter, abelt engaging said structures, a casing enclosing said structures andthe belt, a load driving means operated by one of the pulley structuresand extending out of the casing, a source of power projecting from thecasing and having a rotor for driving the other structure, meansoperated by the source of. power and supported by the rotor forcirculating a cooling stream of air from the exterior of the casing andthrough the casing, and means providing inlet and outlet passages forsaid stream of air between the interior and the exterior of the casing.

2. In a variable speed power unit, a pair of pulley structures, at leastone of said structures having a variable effective diameter, a beltengaging said structures, a casing enclosing said structures and thebelt, a load driving means operated by one of the pulley structures andex-' tending out of the casing, a source of power outside the casingincluding a housing and arranged to drive the other structure, meansforming passages between the interior and the exterior of the housing,fan means operated by the source of power for circulating cooling airthrough said "structures and the belt, a load driving means operated byone of the-pulley structures and extending out of the casing, a sourceof power projecting from the casing and having a rotor for driving theother structure, means operated by the source of power and supportedoutside of said casing for circulating a cooling stream of air from theexterior of the casing and through the casing, and means providing inletand outlet passages for said stream of air between the interior and theexterior of the casing.

4. In a variable ratio transmission, a shaft, a .pulley structure inaxial driving relation to said shaft, said pulley structure including apair of relatively axially adjustable sections with opposed inclinedfaces, forming by relative axial adjustment, variable effective pulleydiameters,

a pair of bearing structures to support the shaft rotatably, speedadjusting mechanism adapted to vary the axial distance between thesections of said pulley structure and including means to support one ofsaid bearing structures, a cage to support the other bearing structure,means forming a lower frame member adapted to support said speedadjusting mechanism and said cage, means forming an upper frame memberadapted to secure the speed adjusting mechanism and the cage in thelower member, when the frame members are in assembled relationship, andmeans to secure said members in assembled relationship, said framemembers being joined substantially along a plane passing through theaxis of said and having a housing, bearings to support the shaftrotatably and supported by said housing, means form-ing a lower framemember adapted to support the housing, means forming an upper framemember adapted to secure the housing in said lower member when the framemembers are in assembled relationship, and means to secure said membersin .assembled relationship, said frame members being joinedsubstantially along a plane passing through the axis of said shaft,whereby the source of power together with the shaft and pulley may beremoved as unit from the frame.

6. In a variable ratio transmission, a shaft, a pulley structure inaxial driving relation to said shaft, said pulley structure including apair of relatively axially adjustable sections with opposed inclinedfaces, forming by relative axial adjustment, variable effective pulleydiameters, bearing structures to support the shaft rotatably, speedadjusting mechanism adjacent one end of the shaft and having a housingcoaxial with the shaft, one of said bearing structures being supportedin the housing, means spaced from said housing and secured theretoforming a supporting surface about the shaft, a cage to support theother bearing structure, and a casing having means to support said cageand having a surface to cooperate with the said supporting surface andthereby support the speed adjusting mechanism, there being openingsbetween said surface on the housing and the housing, whereby theinterior of the casing is in communication with the space surroundingthe housing, said casing being divided into upper and lower memberssubstantially along a plane passing through the axis of said shaft,whereby, when the upper and lower members are in assembled relationship,the means forming a supporting surface on the housing as well as thebearing cage are secured between them, and when they are disassembledsaid shaft and pulley structure together with the bearings and speedadjusting mechanism may be removed as a unit from the frame, and meansto secure said upperand lower members in assembled relationship.

7. In a variableratio transmission, a shaft, a pulley structure mountedon said shaft, a source of power having a housing and in axial driving yin said adapter member whereby the interior of the casing is incommunication with the interior of the housing, said casing beingdivided into upper and lower members substantially along a planepassing'through-the axis of said shaft, whereby when the upper and lowermembers are in assembled relationship the adapter member is clampedbetween them, and when they are disassembled the source of powertogether with the v shaft and pulley may be removed as a unit from thecasing, and means to secure said upper and lowermembers in assembledrelationship.

8. In a variable ratio transmission, a driven shaft, a driving shaft, apair of pulley structures respectively associated with said shafts, atleast one of said pulley structures having a pair of relatively axiallyadjustable sections with opposed inclined belt engaging faces forming byrelative axial adjustment, variable efiective pulley diameters, speedadjusting mechanism associated with said driven shaft to axially adjustthe sections of said variable diameter pulley structure, and having ahousing with a supporting surface formed thereon about 'the drivenshaft, said housing supporting a bearing for said driven shaft, a sourceof power in axial driving relation with said driving shaft and includinghearings to support said driving shaft, means forming a supportingsurface on said source of power about the driving shaft, and a framehaving surfaces formed thereon adapted to cooperate with the supportingsurfaces on said housing and said source of power, said surfaces havingcorresponding dimensions and said frame being divided into upper andlower members substantially in the plane of the axes of the shafts,whereby, when the upper and lower members are in assembled 80relationship, the housing and the source of power are clamped betweenthem, and when they are disassembled the source of power together withits shaft and pulley, and the driven shaft with its pulleyand speedadjusting mechanism, may be removed each as a unit from said frame and.be interchanged in position with respect to the frame, and means tosecure said upper and lower members in assembled relationship.

9. In a variable speed power unit, a pair of pulley structures, at leastone of said structures having a variable effective diameter, a beltengaging said structures, a casing enclosing said structures and thebelt, a'load driving ,means operated by one of the pulley structures andextending out of the casing, an electric motor for driving the otherstructure and having a stator with a frame, and an adapter member,comprising a hollow shell and a transverse partition wall therein, forsupporting said electric motor on said casing, there being an opening insaid member whereby the interior of the casing is in communication withthe space in the adapter member on one side of said wall, there being anopening in said wall whereby said space is-in communication with theinterior of the frame, said member having an opening whereby said spaceis in communication with the medium surrounding the unit, said memberalso having an opening whereby the interior of said frame is incommunication with the medium surrounding the unit.

DON HEYER.

